The U.S. Environmental Protection Agency (EPA) and other federal, state and local agencies have collected extensive environmental monitoring data from the World Trade Center site and nearby areas in Manhattan, Brooklyn and New Jersey. Since September 11, EPA has taken samples of the air, dust, water, river sediments and drinking water and analyzed them for the presence of pollutants that might pose a health risk to response workers at the World Trade Center site and the public. The samples are evaluated against a variety of benchmarks, standards and guidelines established to protect public health under various conditions. EPA is collecting data from 17 fixed monitors in and around ground zero and is using portable sampling equipment to collect data from a range of locations.

Results as of 6:00 p.m. on 10/15

Bulk Samples:

Asbestos - Two dust samples from inside a building within the World Trade Center site were collected on October 10, one sample contained 1.10% asbestos (chrysotile).

Ambient Air Sampling:

VOCs - Sampling for volatile organic compounds (VOCs) was conducted on October 13 and October 14 in the smoke plume within the debris pile at ground zero. Benzene exceeded the OSHA time-weighted average permissible level at two locations, on both days. Benzene was not detected in the breathing zone (approximately 5 to 6 feet above-ground) at three locations several blocks from ground zero.

PM 2.5 - Monitoring for fine particulate matter (particles less than 2.5 micrometers in diameter) was conducted from October 12 to October 13 at Pace University, the Borough of Manhattan Community College and the U.S. Coast Guard building, located in Battery Park. All 24-hour average values were below the National Ambient Air Quality Standards (65 ug/m3) for all stations.